Welcome screen shows /init tip when .claude/CLAUDE.md exists

Description

The welcome screen shows the "Run /init to create a CLAUDE.md file" tip (in warning color) even when a valid .claude/CLAUDE.md file exists and is correctly loaded by the runtime. The detection logic only checks for CLAUDE.md at the project root, missing the officially supported .claude/CLAUDE.md location.

Steps to Reproduce

1. Create a project directory with .claude/CLAUDE.md (but no root-level CLAUDE.md)
2. Launch Claude Code in that directory
3. Observe the welcome screen

Expected Behavior

The welcome screen should recognize .claude/CLAUDE.md as a valid CLAUDE.md file and not show the "/init" creation tip.

Actual Behavior

The welcome screen displays "Run /init to create a CLAUDE.md file" in warning color, implying no CLAUDE.md exists — even though .claude/CLAUDE.md is present and is correctly loaded by the runtime (its contents appear in the assistant's system context).

Notes

• The runtime loader works correctly — .claude/CLAUDE.md is found, loaded, and its contents are injected into the system prompt as expected.
• Only the welcome screen tip detection is affected.
• Both ./CLAUDE.md and ./.claude/CLAUDE.md are documented as equivalent project-level locations for instructions.